fix pypa#1419 PEP420: cleanup code refactor markers

setuptools/tests/markers.py

@@ -0,0 +1,10 @@
+import pytest
+from setuptools.extern.six import PY2, PY3
+
+__all__ = [
+  'py2_only', 'py3_only'
+]
+
+py2_only = pytest.mark.skipif(not PY2, reason="Test runs on Python 2 only")
+py3_only = pytest.mark.skipif(not PY3, reason="Test runs on Python 3 only")
+

setuptools/tests/test_config.py

@@ -5,9 +5,7 @@
 from setuptools.dist import Distribution, _Distribution
 from setuptools.config import ConfigHandler, read_configuration
 from setuptools.extern.six import PY2, PY3
-
-py2_only = pytest.mark.skipif(not PY2, reason="Test runs on Python 2 only")
-py3_only = pytest.mark.skipif(not PY3, reason="Test runs on Python 3 only")
+from setuptools.tests.markers import py2_only, py3_only
 
 class ErrConfigHandler(ConfigHandler):
     """Erroneous handler. Fails to implement required methods."""
@@ -610,8 +608,8 @@ def test_find_namespace_directive_fails_on_py2(self, tmpdir):
         )
 
         with pytest.raises(DistutilsOptionError):
-          with get_dist(tmpdir) as dist:
-            dist.parse_config_files()
+            with get_dist(tmpdir) as dist:
+                dist.parse_config_files()
 
     @py3_only
     def test_find_namespace_directive(self, tmpdir):

setuptools/tests/test_find_packages.py

@@ -7,10 +7,10 @@
 
 import pytest
 
+from setuptools.tests.markers import py3_only
+
 from setuptools.extern.six import PY3
 from setuptools import find_packages
-
-py3_only = pytest.mark.xfail(not PY3, reason="Test runs on Python 3 only")
 if PY3:
   from setuptools import find_packages_ns